It depends on your starting point.
Is he also breastfed?
How long does he sleep at a time?
Had he ever slept on his own?
How many wakes are you having per night?
How many naps in a day?
How active is he in a typical day?
Does he eat well?
Putting him in a cot all alone after having you all his life is harsh and cruel imo. Most people have a routine or comfort to help them get to sleep. I like to cuddle with my dp then wiggle away. I struggle to get to sleep if this routine is broken 🤷♀️ I don't think treating small babies with contempt is very nice, they need comfort and to know they're not alone/abandoned.
Anyway. We did it in stages over multiple weeks.
Dad would cuddle him to sleep for nap times and put him in his cot.
I would feed to sleep at night and then transfer to cot. If he woke up immediately I'd try again. If he woke up after a little while dad would go in for a cuddle. Anywhere between 5-30 minutes, just to warn you. If he woke at past 2/3am I'd just take him into bed with us.
He is now 21 months old and we stopped breastfeeding 2 months ago so the routine is:
Mum brushes teeth.
Dad gets him dressed in PJ's.
Mum reads bedtime story X2.
Turn on musical pip the panda and its light.
Has a drink of water.
Dad cuddles on the rocking chair.
He used to need to be cuddled to sleep or near sleep, he now wants to go in his cot to his stuffed toys after 5-10 minutes and wriggles around getting comfy.
He will cry and need extra care and attention if he is teething or ill etc.